1. Field of the Invention
The present invention relates to a reticle used for a photo lithography process, more particularly to a reticle which can detect precisely a reticle rotation error.
2. Information Disclosure Statement
In general, a stepper is used for a photo lithography process. A reticle 10, as shown in FIG. 1, mounted in the stepper has a quartz substrate 1, scribe lane zone 2 and a plurality of pattern areas 3. The reticle 10 is moved to a direction of X or Y in FIG. 1 by operation of the stepper. When the reticle 10 and the wafer are loaded in the stepper, an exposure process for the wafer is performed. Here, a unit stepping distance to direction of X is X1 and, a unit stepping distance to direction Y is Y1. The reticle 10 must be aligned to confront with a product die of the wafer. However, when the reticle 10 is moved to direction of X or Y, a reticle rotation error may occur. The ordinary reticle 10 shown in FIG. 1 can not detect the reticle rotation error.